Yellow/Brown Spots On Leaves

[gmphoto]

Hello, I am new to this website and a novice orchid grower.

The phalaenopsis (Phal A) I have had for a year started to show signs of something wrong this summer. A few of the leaves have large speckled brown areas along with splitting down the center of the leaf. Also, there is an area that has a brown spot in the middle and yellowing around it.

I recently purchased another phalaenopsis (Phal B). Within a couple weeks it has developed large brown patches with yellowing around it.

Could this be some sort of disease? Please Help!

I have attatched several photos the fist three are from Phal A and the last two are from Phal B